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CHAPTER FOUR
Generation Side Control
As presented in Section 1.3, broad research has been concluded on load
side control. One of the main drawbacks of load side control is that each
load needs a special converter which has to guarantee stability and this
makes the usage of common off-the-shelf components not possible. The
complex internal dynamics of parallel connected converter components
(e.g., power sources) limit the application of classical control theory as
was shown in Ref. [1], where linear-controlled converters exhibited cha-
otic behavior.
Therefore, the goal is to design a generation control system that meets
the operational objectives of the medium voltage direct current (MVDC)
power system in presence of wide variations of load or generation capacity.
The idea of this approach is inspired by the adaptive control of the genera-
tor side interface converters, which compensates for the negative resistance
behavior of the loads at every operating point to maintain system-wide
stability [2]. To achieve this goal in a multiconverter environment several
approaches are proposed and described mathematically in this chapter.
Their classification can be seen in Fig. 4.1. Those algorithms will be later
described throughout Chapter 7, Hardware in the Loop Implementation
and Challenges. But before coming to the control algorithms a system
description of the Integrated Shipboard Power Systems (ISPSs) including
the circuit basis will be given.
4.1 MVDC SHIPBOARD POWER SYSTEMS
In Chapter 1 the transition from load side control to generation
side control in MVDC ISPS was previously highlighted. Therefore,
before introducing any generation side control scheme a more detailed
look into the application case and its characteristics is necessary.
The generating devices are connected to the MVDC bus via a multi-
stage solution consisting of a rectifier and a DC DC converter. Recently,
the usage of a single stage solution implemented via modular multilevel
Modern Control of DC-Based Power Systems. © 2018 Elsevier Ltd.
DOI: https://doi.org/10.1016/B978-0-12-813220-3.00004-1 All rights reserved. 103
